Electric railway-signal



(No Model.) ,2 sheets-sheet 1.

E.T.HARVEY. ELECTRIC RAILWAY SIGNAL.

No. 446,917. Patented Feb. 24,1891.

(No Model.) 2 Sheets-Sheet 2.

E. T. HARVEY. ELECTRIC RAILWAY SIGNAL. No. 446,917. v Patented Feb. 24,1891.

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EARL 'I.I-IARVEY, OF CHICAGO, ILLINOIS.

ELECTRIC RAI LWAY-SIGNAL.

SPECIFICATION forming part of Letters Patent No. 446,917, dated February 24, 1891.

Application filed November 6, 1888. Serial No, 290,080. (No model.)

To aZ Z whom, it may concern:

Be it known that I, EARL T. HARVEY, a citizen of the United States, residing at Chicago,

in the county of Cook and State of Illinois, have invented certain new and useful Improvements in an Electric Railway-Signal, of which the following is a full, clear, and exact description, that will enable others to make and use the same, reference being had to the accompanying drawings, forming a part of this specification.

The object of this invention is to provide an electric signaling arrangement for railwaytrains, whereby the engineer receives an O. K. signal at different or predetermined points along the line of the road, the road being divided up into sections, each section having an independent circuit. The circuits are normally open and the arrangement such that the engineer receives an O. K. signal instead of a danger-signal, as will be hereinafter set forth.

Figure 1 is a diagram showing a track-section and parts of the adjoining sections; Fig. 2, a vertical section of a locomotive-pilot embodying a part of my improvement; Fig. 3, a perspective of a locomotive-pilot, showing the arrangement of and means for closing the circuit and the signal device or bell; Fig. 4, a detail of one of the signal-posts-located in the circuit; Fig. 5, a diagram or plan of track-section, showing the arrangement of the circuit-wires. I

Referring to the drawings, A A represent the railway track-rails, having a break in them, as at a, between each section and circuit, this broken end of the track-section being connected and made continuous by any suitable insulating arrangement.

B represents a battery, and C O the wires connecting the same with the insulated ends a. a of the track-rails.

In the path of the wires C O and convenient to the side of the track are placedthe visual signal-posts D D, provided with the metallic strip a covering two sides and the top of said posts and forming a continuous circuit for the battery-wires. These posts are'not essential to the operation of the signal device proper, but are merelyvisual signals to indicate in advance the time and place of receiving the O. K. signal. These posts might just as well be out of the circuit as in it, and are only placed in the pathway of the wires for the reason that were they intentionally removed the circuit would be broken, thus af fording an additional precaution.

The signal-circuit wires E E,in connection with the battery-wires and track-rails, make the complete circuit of each section. The course of the current from the battery is through the positive and negative wires 0 O and the track-rails to the opposite end of the section, and returns through the wires E E to the electric contact-plates b b b I), located at the batteryend of thesection and secured to the wooden cross-bars F F. The wires E E also connect with the companion contact-plates I) Z) Z) I), located at the opposite end of the section, thus providing for the giving of two distinct audible'signals at either end of the section and within a few moments of each other, in ac cordance with the distance between the contact-plates. WVhen the circuit is closed, the current first passes through the whole section before the O. K. signal is sounded on the engine just passing onto the section. Now if the section just entered is not clear-that is, if another train is on the trackthe current would be short-circuited and no audible safety-signal sounded on the engine last entering the section. Thus the engineer would know that the way was not clear. In case of abroken rail no safety-signal would be sounded on the engine passing onto either end of the section. The circuit is normally open, and is closed by the signal-keys d (I, attached to the pilot or other convenient part of the locomotive, and which are electrically connected with the alarm device II, located in the engine-cab. The keys (Z d curve downwardly, the extreme ends being bent upwardly and over upon themselves, (see Fig. 3,) leaving the under side rounded, so as to freely slide over the stationary plates 1) b, no matter which way the locomotive may be moving. The different sections are not electrically connected, each section being independent of the other, so that the signal-connection need not be used on the whole length of the road if not desired, but only at the more dangerous points. The signal contact-plates of each section extend into and are located between the trackrails of the adjoining sections.

In operation, suppose the stationary plates 1) b to be located, say, one thousand or fifteen hundred feet from the end of the section which the locomotive is approaching. The circuit is closed by the keys d d on the pilot coming in contact with the stationary plates 1) Z), lying in the pathway of the same between the track-rails, and the audible signal given, which is a safety-signal and indicates that the next section is clear. A little later the circuit-closing keys on the locomotive strike the stationary companion plates 1) Z), placed as near as possible to the ends of the trackrails forming the terminus of that section, when a second audible signal is sounded, which is also a safety-signal, and informs the engineer that nothing has passed onto the section ahead since receiving, the first signal. If no audible signal is received at the proper time, then the engineer knows that the next section is not clear and can govern himself accordingly, and thereby avoid what might otherwise cause an accident.

In the application of my improved signal device, where double tracks are used and the travel on each line is in one direction only, the circuit-wires E E are dispensed with, the contact-plates being used and electrically connected with one end only of the track-rails,

'and that at the opposite end of the section from where the battery is located.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is

1. In an electric signal for railways wherein the road is divided into independent electric signal sections, the combination, with the track-rails at one end of a section, of the battery-wires connected to thebroken and insulated ends of said rails, the circuit-wires connected to the rails at the opposite end of the section and returning to the battery end, and the contact signal-plates located at each end of a section and electrically connected with reference to each other, substantially as and for the purpose set forth.

2. In an electric signal for railways wherein the road is divided into sections, as described, the combination, with a track-section insulated from the joining sections, of an electric battery, the wires connecting the battery with the track-rails at one end, the contact-plates located at each end of the section, the circuitwires connecting the track-rails and the series of contact-plates with reference to each other, and the circuit-closing keys attached to a locomotive and adapted to have contact with the series of plates when passing over the same, whereby a safety-signal. is sounded it the roadway is clear, substantially as and for the purpose set forth.

EARL 'l. HARVEY. Witnesses:

L. M. FREEMAN, L. B. COUPLAND. 

